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Poster: dead-head_Monte Date: Feb 1, 2012 9:28am
Forum: occupywallstreet Subject: New NASA study confirms man-made influence over global warming

Earth's Energy Budget Remained Out of Balance Despite Unusually Low Solar Activity - Published on NASA's website 30 Jan 2012

A new NASA study confirms the fact that greenhouse gases generated by human activity - not changes in solar activity - are the primary force driving global warming.

200px-NASA_logo.svg.pngThe study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of solar energy absorbed by Earth's surface and the amount returned to space as heat. The researchers' calculations show that, despite unusually low solar activity between 2005 and 2010, the planet continued to absorb more energy than it returned to space.

James Hansen, director of NASA's Goddard Institute for Space Studies (GISS) in New York City, led the research. Atmospheric Chemistry and Physics recently published the study.

Total solar irradiance, the amount of energy produced by the sun that reaches the top of each square meter of the Earth's atmosphere, typically declines by about a tenth of a percent during cyclical lulls in solar activity caused by shifts in the sun's magnetic field. Usually solar minimums occur about every eleven years and last a year or so, but the most recent minimum persisted more than two years longer than normal, making it the longest minimum recorded during the satellite era.

Pinpointing the magnitude of Earth's energy imbalance is fundamental to climate science because it offers a direct measure of the state of the climate. Energy imbalance calculations also serve as the foundation for projections of future climate change. If the imbalance is positive and more energy enters the system than exits, Earth grows warmer. If the imbalance is negative, the planet grows cooler.

Hansen's team concluded that Earth has absorbed more than half a watt more solar energy per square meter than it let off throughout the six year study period. The calculated value of the imbalance (0.58 watts of excess energy per square meter) is more than twice as much as the reduction in the amount of solar energy supplied to the planet between maximum and minimum solar activity (0.25 watts per square meter).

"The fact that we still see a positive imbalance despite the prolonged solar minimum isn't a surprise given what we've learned about the climate system, but it's worth noting because this provides unequivocal evidence that the sun is not the dominant driver of global warming," Hansen said.

According to calculations conducted by Hansen and his colleagues, the 0.58 watts per square meter imbalance implies that carbon dioxide levels need to be reduced to about 350 parts per million to restore the energy budget to equilibrium. The most recent measurements show that carbon dioxide levels are currently 392 parts per million and scientists expect that concentration to continue to rise in the future.

619624main_solar%20irradiance%20graph.jpg

A graph of the sun's total solar irradiance shows that in recent years irradiance dipped to the lowest levels recorded during the satellite era. The resulting reduction in the amount of solar energy available to affect Earth's climate was about .25 watts per square meter, less than half of Earth's total energy imbalance. (Credit: NASA/James Hansen)

Climate scientists have been refining calculations of the Earth's energy imbalance for many years, but this newest estimate is an improvement over previous attempts because the scientists had access to better measurements of ocean temperature than researchers have had in the past.

The improved measurements came from free-floating instruments that directly monitor the temperature, pressure and salinity of the upper ocean to a depth of 2,000 meters (6,560 feet). The network of instruments, known collectively as Argo, has grown dramatically in recent years since researchers first began deploying the floats a decade ago. Today, more than 3,400 Argo floats actively take measurements and provide data to the public, mostly within 24 hours.

Hansen's analysis of the information collected by Argo, along with other ground-based and satellite data, show the upper ocean has absorbed 71 percent of the excess energy and the Southern Ocean, where there are few Argo floats, has absorbed 12 percent. The abyssal zone of the ocean, between about 3,000 and 6,000 meters (9,800 and 20,000 feet) below the surface, absorbed five percent, while ice absorbed eight percent and land four percent.

The updated energy imbalance calculation has important implications for climate modelling. Its value, which is slightly lower than previous estimates, suggests that most climate models overestimate how readily heat mixes deeply into the ocean and significantly underestimates the cooling effect of small airborne particles called aerosols, which along with greenhouse gases and solar irradiance are critical factors in energy imbalance calculations.

"Climate models simulate observed changes in global temperatures quite accurately, so if the models mix heat into the deep ocean too aggressively, it follows that they underestimate the magnitude of the aerosol cooling effect," Hansen said.

Aerosols, which can either warm or cool the atmosphere depending on their composition and how they interact with clouds, are thought to have a net cooling effect. But estimates of their overall impact on climate are quite uncertain given how difficult it is to measure the distribution of the particles on a broad scale.

The new study suggests that the overall cooling effect from aerosols could be about twice as strong as current climate models suggest, largely because few models account for how the particles affect clouds.

A chart shows the global reach of the network of Argo floats
(Credit: Argo Project Office) › Larger image

619617main1_Argo%20chart-670.jpg

"Unfortunately, aerosols remain poorly measured from space," said Michael Mishchenko, a scientist also based at GISS and the project scientist for Glory, a satellite mission designed to measure aerosols in unprecedented detail that was lost after a launch failure in early 2011.

"We must have a much better understanding of the global distribution of detailed aerosol properties in order to perfect calculations of Earth's energy imbalance," said Mishchenko.

Related Links

Atmospheric Chemistry and Physics Study

James Hansen Biography

Argo Project Office

NASA-led Study Solves Case of Earth's 'Missing Energy'

World of Change: Solar Activity

Adam Voiland — NASA's Earth Science News Team


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Poster: rastamon Date: Feb 1, 2012 9:43am
Forum: occupywallstreet Subject: Re: New NASA study confirms man-made influence over global warming

Oh holy NASA! Another take >>

http://www.iceagenow.com/Sunspots_and_global_cooling.htm

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Poster: dead-head_Monte Date: Feb 1, 2012 12:22pm
Forum: occupywallstreet Subject: Re: New NASA study confirms man-made influence over global warming

What are NASA Scientists, and 97% of the World's Leading Climate Scientists saying? Bill McKibben is an environmental author of a dozen books about the environment. He says, "Warm air holds more water vapor than cold air. The Earth is getting warmer now. The planet's climate is 4% wetter than it was forty years ago. This causes devastating weather extremes that are linked to human-caused climate change." McKibben was interviewed about this last year.

Atmospheric CO2 levels have increased dramatically since 1900, when The Industrial Revolution took hold. Today these CO2 levels are being measured at 392 ppm. Increasing our annual CO2 emissions cannot be sustained.

• Conclusion about Global Warming Facts Reported by The Mainstream Media:
Mark Hertsgaard is an investigative reporter who has worked for more than 20 years on climate change. He is the environmental correspondent for The Nation magazine. His new book is Hot: Living Through the Next Fifty Years on Earth.

In an interview last year Mark Hertsgaard says, "[Here's] the problem. They [U.S. Senator James Inhofe, Fox News, U.S. Mainstream Media] are climate cranks. They like to be called "climate skeptics." And the media, I’m very sorry to say — the mainstream media, at least — calls them climate skeptics. They are not skeptics. Genuine skeptics are invaluable to science. That’s how science progresses, is with skepticism. But a true skeptic can be persuaded by evidence. They cannot. They have made up their minds for economic reasons or ideological reasons that they’re not going to believe in this. And because our country has allowed them to dominate the debate for 20 years, we’re now stuck with 50 more years of rising temperatures."
It’s very important to stay calm. If you got upset about any of this, you might forget how important it is not to disrupt the record profits of our fossil fuel companies. If worst ever did come to worst, it’s reassuring to remember what the U.S. Chamber of Commerce told the Environmental Protection Agency in a recent filing: that there’s no need to worry because “populations can acclimatize to warmer climates via a range of behavioral, physiological, and technological adaptations.” I’m pretty sure that’s what all the Sheeple are telling themselves.